The present invention relates to an electric distributor assembly preferable for movable means such as vehicles including automobiles, which are required to be lightened, and in particular, to an electric distributor assembly made by an aluminum twisted cable conductor and an aluminum-made terminal attached to the cable conductor (hereafter, the term xe2x80x9caluminumxe2x80x9d is often noted as xe2x80x9cAlxe2x80x9d).
Copper assemblies have conventionally been used as distribution assemblies for automobiles in the form of harness wires, battery cables, and others mounted thereon. Each assembly has not only a distribution cable of which conductors are copper twisted wires but also copper terminals coupled to the cable. In such circumstances, a recent trend is that a new type of automobile of which drive power is partly or entirely supplied by electric power has been under development. One key factor in the development is what type of electric distributor assembly should be used. It has been considered that an Al assembly including a distribution cable made of Al-twisted wires and Al terminals coupled to the cable should be used for such electric distributor assembly, because there is an advantage of being lighter in weight which stems from aluminum.
However, the Al assembly has various problems. In other words, using the Al-made assembly for a long time causes a thick oxide layer generated between connected boundary faces of the Al twisted-wire conductor and each Al terminal. Additionally, in a corrosive environment, the Al-made assembly is easier to be corroded. If being placed in such a corrosive environment, contact resistance between the Al-made twisted-wire conductor and the Al terminal increases little by little, thus a connection characteristic therebetween being spoiled in course of time.
To overcome those problems, plating the Al-made twisted wires with a corrosion resistant metal like Ni was conceived, but has not been practiced because of the problems in the production process.
Additionally, the Al electric distributor assembly is poor in flexibility, thus making handling of the distribution cable difficult and causing cracks within the terminal while the assembly is formed or mounted.
An object of the present invention is to provide a distribution cable assembly for movable means whose cable is easier to be handled, whose terminals are excellent in workability, and which has an excellent connection characteristic between an Al twisted-wire conductor of the cable and each Al terminal.
A first embodiment of the present invention is an electric distributor assembly comprising a distribution cable composed of an insulation-coated twisted-wire conductor and a connecting terminal connected to one end of the conductor, wherein
the twisted-wire conductor is made of an aluminum metal or an aluminum alloy of which conductivity is 50% or more under IACS,
the connecting terminal connected to the twisted-wire conductor is made of a metal, and
the twisted wire conductor and the connecting terminal are connected by pressure welding with ultrasonic vibrations.
A second embodiment of the present invention is an electric distributor assembly in which the aluminum alloy composing the twisted-wire conductor consists of Zr: 0.03 to 0.4 wt %, Fe: 0.05 to 0.2 wt %, and Si: 0.05 to 0.2 wt % and further includes in total 0.003 to 0.05 wt % of one or more elements selected from Be, Sr, Mg, Ti and V, and the balance consists of Al and unavoidable impurities.
A third embodiment of the present invention is an electric distributor assembly in which the metal for the connecting terminal connected to the twisted-wire conductor is an aluminum metal or aluminum alloy whose elongation is 20% or more.
A fourth embodiment of the present invention is an electric distributor assembly in which the aluminum alloy composing the connecting terminal consists of Zr: 0.03 to 0.4 wt % and Si: 0.05 to 0.15 wt % and the balance consists of Al and unavoidable impurities.
A fifth embodiment of the present invention is an electric distributor assembly in which the aluminum alloy composing the terminal includes Mg: 0.3 to 1.8 wt %, Si: 0.15 to 1.5 wt %, Fe: 0.1 to 1.0 wt %, and Cu: 0.05 to 0.5 wt % and further includes in total 0.03 to 0.6 wt % of one or more than one selected from Mn, Cr and Ti, and the balance consists of Al and unavoidable impurities.
A sixth embodiment of the present invention is an electric distributor assembly in which the metal for the terminal is coated on its surface with Ni or an nickel alloy with a thickness of 5 xcexcm or less.
A seventh embodiment of the present invention is an electric distributor assembly comprising an electromagnetic shielding metal layer covering an outer surface thereof and an insulation-coated layer covering an outer surface of the metal layer.
An eight embodiment of the present invention is an electric distributor assembly in which the electromagnetic shielding metal layer is composed of a reticulated member made of aluminum or aluminum alloy.